A pier mainly consists of a hood and a pier body. The hood plays a role of dispersedly and uniformly transmitting a higher but concentrated force from a bridge span support to the pier body and a pile cap body. Therefore, the hood shall be made by a material with higher strength. In addition, the hood shall also have a larger plan view size to provide a necessary working surface for construction, girder erection and maintenance. Both the pier body and the pile cap body are major structures for supporting the bridge span, which not only bear all the loads coming from the bridge span structure, but also directly bear earth pressure, water impact force, ice pressure, ship impact force and other various loads. Therefore, both the pier body and the pile cap body have sufficient strength, rigidity and stability, and are important parts of a bridge structure.
Commonly used piers include two types, wherein one is a gravity type pier, and the other is a light type pier. The gravity type pier is generally a concrete or stone-built solid structure. An upper portion of the pier body is provided with a pier cap and a lower portion thereof is connected with a foundation. The gravity type pier is characterized by fully utilizing anti-pressure properties of masonry materials, bearing outer forces from a vertical direction and a horizontal direction by larger cross-section size and weight thereof. The gravity type pier has the advantages of firm and durable performance, easiness in construction, convenience in obtaining materials, steel-saving, or the like. The disadvantages of the gravity type pier are as follows: the amount of masonry is large and the appearance thereof is bulky and heavy, so that an effective aperture under the bridge is reduced, and the foundation load is increased; and it is particularly unfavorable when the pier is higher and the foundation bearing capacity is lower. However, the light type pier has the advantages of light and beautiful appearance and less amount of masonry, can lighten the foundation load, saves foundation works, is convenient to construct by an assembled structure or a climbing form, is beneficial for accelerating the construction progress, and enhances the labor productivity, or the like. The disadvantage of the light type pier is that the structure of the pier in some cases is more complex, so that a certain degree of difficulty is present in construction, and a certain degree of difficulty is also present in construction schedule and control.
It is obvious that to design a novel assembled type pier column structure has become a technical problem to be solved urgently.